He read that Japan sells more adult diapers than baby ones. Most people would file that under sad. He filed it under opportunity, and built a company on it.
AT Nakanishi runs Triple W, the company behind DFree, a small wearable that does something no gadget had done before: it watches the body with ultrasound and tells you, gently, when it is time to head to the restroom. He is its founder and chief executive, and he is the first to point out that he is not an engineer. He built a hardware company anyway.
The shorthand version of his story moves fast. A year at UC Berkeley studying finance and global business. An idea that would not leave him alone. A return to Japan, where in 2015 he started Triple W with a roster of co-founders pulled straight from his own life - high school friends, college friends, the people who would actually answer the phone at 2 a.m. By 2018 the product had crossed the Pacific in the other direction, landing in the United States as the first device of its kind. By 2019 it was holding a Best of CES trophy.
What makes Nakanishi worth watching is not the trophy. It is the choice behind it. He went looking for a market everyone else found uncomfortable, and treated that discomfort as a moat. Big, unglamorous, underserved problems do not attract crowds of founders. That is exactly why he liked it.
Full name: Atsushi Nakanishi
Role: Founder & CEO, Triple W (DFree)
Base: Berkeley, California
Roots: Japan; Tokyo HQ
Study: UC Berkeley, finance & global business
Known for: The world's first personal wearable ultrasound sensor
To develop a completely new product from ground zero was much more difficult than I thought.
The detail that lit the fuse was a number on a page. In Japan, sales of adult diapers had quietly overtaken sales of baby diapers. For most readers that is a demographic footnote about an aging country. For Nakanishi it was a flare in the dark - millions of people, a very large market, and almost nobody building anything new for it.
So he asked the founder's version of the right question: what if this were predictable? Not managed after the fact, but seen coming. That single reframing - from coping to forecasting - is the seed of everything Triple W has built. The company took the physics of an ultrasound scan, the kind used in hospitals, and shrank it into a sensor you can wear, paired with an app that does the watching for you.
It is a deceptively simple pitch with a brutally hard build. Hardware is unforgiving. Sensors lie. Apps crash. And Nakanishi, by his own admission, started without an engineering degree or a deep war chest. He had a problem worth solving and a group of friends willing to solve it with him. In startup arithmetic, that turned out to be enough.
A crowded problem is a fair fight. An ignored one is a head start.
The founding team was not assembled from a recruiter's spreadsheet. "All of the members are my friends," he says - high school and college friends who signed up for a hard, unfashionable problem because he asked.
Early prototypes were validated the hard way, by the team wearing the device for days to see whether the sensor actually held up. Conviction you can measure in inconvenience.
He moved the company from San Francisco to Tokyo when investor interest was stronger there, then kept one foot planted in the US market. Pragmatic, not sentimental, about where a startup should live.
No chasing trends for their own sake. The product solves one concrete thing well before it tries to do ten. Simplicity as a strategy, not a limitation.
"DFree solves all that by making it user friendly, portable, and also affordably priced," he says. A device that helps nobody if only a few can afford it.
He frames the wearable ultrasound sensor as a platform, with ambitions to read other vital organs over time - one product as the opening move, not the whole game.
Nakanishi does not talk like a man building a single gadget. He talks about a sensing platform - the same non-invasive ultrasound approach pointed at other parts of the body, turning a wearable into a quiet, predictive instrument for everyday life.
It is an ambitious arc for a company that started with one friend's idea and a statistic about diapers. Then again, the founders who change a category tend to be the ones who started somewhere nobody was looking.
PRAGMATIC · PERSISTENT · PROBLEM-FIRST · TEAM-LOYAL · UNAFRAID-OF-THE-UNGLAMOROUS